Cody attempted all the 17 questions in a quiz and scored 19 marks. Given that 8 marks were awarded for each correct answer but 5 marks were deducted for each wrong answer. how many questions did Cody answer correctly?
Number of
correct answers |
Marks
awarded |
Number of
wrong answers |
Marks
deducted |
Total
marks |
17
|
17 x 8
= 136 |
0 |
0 |
136 |
16
|
16 x 8
= 128 |
1 |
1 x 5
= 5 |
128 - 5
= 123 |
| 8 |
8 x 8
= 64 |
9 |
9 x 5
= 16 |
64 - 16
= 19 |
Total marks awarded if all the answers are correct
= 17 x 8
= 136
Big difference in marks deducted
= 136 - 19
= 117
Small difference in marks deducted
= 8 + 5
= 13
Number of wrong answers
= 117 ÷ 13
= 9
Number of correct answers
= 17 - 9
= 8
Answer(s): 8
